Question

The equations of the lines through $(-1,-1)$ and making angle ${45}^{\circ }$ with the line $x+y=0$ are given by

• A. $x+1=0$
• B. $x=1$
• C. $y+1=0$
• D. $y=1$

Answer 1

Answer: (A), (C)

$y+1=0$

$x+y=0$ make an angle ${135}^{\circ }$ with +ive direction of $x-$axis.
So, the lines which make $45°$ angle with the line $x+y=0$ will have an inclination of $135°\pm 45°$
$\therefore$ Equation of lines will be $x+1=0,y+1=0$